The Church affirms that human life is sacred
from conception to natural death, thus asserting the inviolability
of all human beings. So, the question is really, are embryos and
clones, if ever produced, human beings?

This question is answered adequately by
philosophy and science. Science shows us that different kinds of
existing things, called a being, belong to specific categories of
being. Among living beings we can determine from the genetic makeup
of the individual what kind of being it is. Human sperm and egg
cells have only half the complement of human genetic material, and a
limited lifespan. They do not replicate and organize themselves in
any way. They are "human" in that they come from human
beings, but they are not human beings. However, after they unite to
form a fertilized ovum all the genetic material that will ever be
needed is present to constitute a human being. Furthermore, other
than needing a special environment at different stages (whether the
womb or the cradle), all that will determine their growth is the
unfolding of the genetic plan contained within and the addition of
nutrients and time. This cannot be said of sperm and egg. Their
independent life is fixed. The life of a human being is not – all
it needs is the right environment, food, water, oxygen and love.
Whether two cells or two billion cells, this is true.

In the case of frozen embryos, if they can be
revived and if they are then still living, then they are human
beings, and all human beings by definition have a soul. Since such
embryos have developed into human children we know this to be true.
The same would be true of clones. If the processes, no matter how
artificial and unnatural, result in a being that is materially human
in makeup and can live and develop into a child, then that child
will have a soul. No creature as materially complicated as a man can
live without the spiritual form which theology calls the soul.